Press Release


First Quasi-Zenith Satellite MICHIBIKI
Injection into the Quasi-Zenith Orbit

September 27, 2010 (JST)

Japan Aerospace Exploration Agency (JAXA)

The Japan Aerospace Exploration Agency (JAXA) has controlled the orbit of the First Quasi-Zenith Satellite "MICHIBIKI" to insert it into the quasi-zenith orbit from the drift orbit starting on September 21 (Japan Standard Time, JST), and the final orbit control operation was performed for about 50 seconds from 6:28 a.m. on September 27 (JST.) After the operation, we have confirmed that the satellite was successfully injected into its preordained quasi-zenith orbit with its center longitude of about 135 degrees through the orbit calculation. The calculation results are as follows.
The MICHIBIKI was launched from the Tanegashima Space Center at 8:17 p.m. on September 11, 2010 (JST.)

Finalized Orbit*
Apogee altitude 38,950km
Perigee altitude 32,618km
Orbit inclination 41.0 degrees
Period 23 hours 56 minutes
Drift rate 0.03 degrees/day (to the east direction)

We will carry out the initial functional verification of the onboard mission devices in cooperation with organizations*1 that perform technological verifications for about three months.

- Drift orbit : The last step orbit prior to the quasi-zenith orbit. The orbit altitude and inclination (angle against the equator) are equal to those of the quasi-zenith orbit, but the longitude of the center of the figure-8 orbit is not above Japan. After being injected into the drift orbit, it will take a few days to maneuver the satellite to have its figure-8 center above Japan, thus it will ultimately fly in the quasi-zenith orbit.
- Quasi-zenith orbit : While the quasi-zenith orbit has the same orbit period of 23 hours and 56 minutes as the geostationary orbit, it can let a satellite stay over Japan longer by taking an elliptical orbit with higher altitude above Japan and flying in a figure-8 orbit.

*1 Geospatial Information Authority of Japan (GSI), National Institute of Advanced Industrial Science and Technology (AIST), National Institute of Information and Communications Technology (NICT), Electronic Navigation Research Institute (ENRI), Satellite Positioning Research and Application Center (SPAC)